1. Field of the Invention
The present inventions relates to pump assemblies utilized in very hazardous installations such as nuclear processing plants or the like and more particularly to pump assemblies in which installation and removal of the drive motor for the pump must be made by remotely operated equipment.
2. Description of the Prior Art
Pump assemblies which are installed in nuclear processing plants to handle solutions or slurries of very highly radioactive materials are often serviced by remote techniques. The cost of this type of maintenance is large and difficult to perform. Even for those plants where radiation is not as severe and maintenance could be performed by direct methods, the initial capital cost may be reduced, but these savings may be offset to a large extent by increased costs related to decontamination and limited permissible working time of maintenance personnel.
In plants for nuclear fuel reprocessing or the like the pump assemblies are installed with remote handling equipment into so-called "canyon" areas where the radiation levels are so high that no one may enter. It is therefore impossible to relubricate or service a conventional pump once it has been installed and placed in service.
The weakest areas of these pump/motor assemblies resides in the deterioration of the lubricant in the pump and motor bearings and the deterioration of the motor insulation due to radiation. Accordingly, a pump/motor assembly which can be serviced by a simple remote arrangement would be a decided advance in the state of the art.